The bacteria Staphylococcus epidermidis, Staphylococcus aureus, and Micrococcus luteus; moreover, Corynebacteria and Mycobacteria are also found.

Coagulase-negative staphylococci (S. epidermidis and other species), the principle constituents of skin microflora, are the predominant etiological agents, followed by S. aureus and group D streptococci (enterococcal and nonenterococcal).

So I suppose you can take swabs of your skin (i.e. underneath a subject's armpit) and other areas and try to identify the pathogen that grows?

You can start you lab report like this:

There are microbes that are indigenous to our body and in particular, our skin. Regardless of pathogenicity, commensal even, these micro-organisms survive the skin-secreted antimicrobial substances and relative dryness to exist symbiotically. Among these microorganisms, Staphylococcus epidermidis and Corynebacteria are found almost 100 percent of the time on the skin. In addition, a potential pathogen, Staphylococcus Aureus is also commonly found on the skin together with Mycobacteria. Although rarely found on skin, there is another microbe, Streptococcus pyogene, which is also a pathogen.

Well, i think I need a list of them before I decide how I can go about doing it. What are the species of mycobacteria commonly found on the human skin? Which species of Streptococcus are commonly found? Enterococcus arent usually found on the skin, they are more on the inside of the body right?

Same for Corynebacteria. What are the major species grown on the skin?

Depending on your level of study (I'm guessing third-year microbiology ), I would mostly focus on two main species, namely staphylococci (Staphylococcus epidermidis and Staphylococcus aureus), which are the principle constituents of skin flora. We know that skin variety provides a rich and diverse habit for bacteria; there is no doubt about that, but literature mainly focuses on these two species of bacteria. My advice, don't complicate things . Nevertheless, Propionibacteria and Staphylococci species are the main species found in sebaceous areas. In moist places on the body, Corynebacteria together with Staphylococci dominate. In dry areas, there is a mixture of species but b-Proteobacteria and Flavobacteriales; they are dominant. Ecologically, sebaceous areas has greater species richness than moist and dry places.

It sure does, thanks. Because the question set to me was to introduce major constitutents of microflora in skin and identify them. So, I have to make sure that I can account for almost most of the major constituents in the skin before I can go into identifying through catalase, oxidase test etc.

Would be nice if you can also recommend some tests for me to identify some of them =).

The chart is a little bit confusing. There are 2 coccus (cluster), I am not really sure whats that use for. I have a couple of Staphylococcal species, so I dont think those oxidase tests are going to be useful.

Does the Bergey's manual tell the major constitutent of skin microflora?

Great. Now I can use it to check for S. Aureus and Epidermis. As for the 3rd species, is it readily found in our skin?

BTW, is Propionibacteria the ones that causes acne? If that is, I think I have to have that in. I know Corynebacteria and mycobacteria are also found the human skin but do not know what special trait they have. Can you help me in identifying them?

Yes, as in P. acnes, the common skin disease acne vulgaris. However, species of Propionibacteria can be found all over the body.

Corynebacteria are small, generally nonmotile, Gram-positive, non-sporulating (although they have club-like ends), pleomorphic bacilli. Due to their snapping type of division, cells often lie in clusters resembling chinese letters. Corynebacteria are chemoorganotrophic, aerobic, or facultatively anaerobic, and they exhibit a fermentative metabolism (carbohydrates to lactic acid) under certain conditions. They are fastidious organisms, growing slowly on even an enriched medium. The best method for isolating and cultivating Corynebacteria is to use sheep blood agar plus one selective medium as the primary plating media. Selective media commonly used are Cystine-Tellurite blood agar or Tinsdale medium. The plates should be ready after 18 to 24 hours of incubation at 37 degrees Celsius in a 5% carbon dioxide-enriched atmosphere.

Skip Mycobacteria because that requires acid-fast staining. Have you performed acid-fast before? Besides, it's not as common as the other ones.

I have checked through the requirements, I need to go to species level. I have to have a list of the bacteria that are found on the Skin Microflora. I have since compiled a list, please see if you can add to it

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